The Science Behind: The Search for Ancient Cities

National Geographic had a fascinating write up in this month’s magazine about a group of archeologists who discovered an apparently untouched city in the remote jungles of Honduras. While the importance of learning about and recording these previously lost civilizations cannot be understated, the method they used to find the ruins is fascinating in itself.

The explorers used a process called lidar (light detection and ranging) shoots hundreds of thousands of pulses of light at the ground, and then maps the way they bounce back in three dimensions. The lidar operators are then able to clean up the image, so to speak, removing brush and trees from the equation to produce a 3-D map of the landscape underneath the jungle. This allows historians to analyze vast tracts of ground that would take weeks to map out by hand, if they could be mapped out at all.

This technology is hugely important for looking for ruins in places not easily accessible by traditional means of exploration. Unfortunately, lidar is hugely expensive. According to the National Geographic story, “For NCALM [the National Center for Airborne LAser Mapping at the University of Houston] to scan just the 55 square miles…would cost a quarter of a million dollars.” While 55 square miles might seem like a decent amount of ground, it’s not when you consider the vastness of the Central and South American jungle — all possible locations for lost and forgotten civilizations.

The story itself is fascinating. Although, according to The Guardian, other archeological experts are quick to point out that the expedition didn’t necessarily find the treasured lost city that they had set out to uncover, what they do find is a testament to a people whose advancement and skill is (I think) often underestimated. The society that the city likely belonged to, the Mosquitia, had developed an impressive culture in their own right, although on a much smaller scale than their Mayan neighbors to the north. You can read about the expidition in the web version of the article here, or in the October 2015 issue of National Geographic.